Flexible LED pixel strings where a number of LED pixels are interconnected by a flexible cable are commonly known in the field of visual solutions. Typically each LED pixel comprises a number of red LEDs, a number of blue LEDs and a number of green LEDs which can be dimmed in relation to each other whereby a large number of colors can be created by each LED pixel as known in the art of additive color mixing and LED video display systems.
Typically the flexible LED pixel strings are coupled to a feeder capable of feeding both power and data to the flexible LED pixel strings. The feeder is typically controlled by a content server or light controller distributing the pixel content to the LED pixel strings. The flexible LED pixel strings can be providing in many different environments and arranged in many different shapes whereby various visual effects can be created by the flexible LED pixel strings.
Typically the flexible LED pixel string comprises a clock signal wire, a data signal wire, a reference potential wire and a power line wire. The LEDs pixels are controlled by the feeder through the string based on an internal proprietary protocol defined by the manufacture of the LEDs or the LED array and the feeder is electrically connected a content server or light controller distributing for instance through a standardized lighting control protocol such as DMX.
For instance the applicant presently provided a flexible LED pixel string named FIexDOT S1. FIexDOT S1 is a lightweight string of individually controllable, bright RGB LEDs useful in creating customized LED video solutions with maximum artistic flexibility and a minimum of effort. The FIexDOT S1 flexible LED pixel string are connected to a feeder which receives a DMX signal and controls the LED pixels based on this DMX signal.
Other companies provides similar systems for instance the company named Philips provides a range of flexible LED pixels string named iColor Flex LMX, iColor Flex MX and eW Flex SLS. These flexible LED pixel strings are also controlled by a controller which can receive DMX signals but witch in addition is capable of receiving control signals through an Ethernet connection. Similar flexible LED pixel string solutions are provide by the companies named Barco (through the system named FLX-24) and Traxon (through system named Dot XL). In general there are many companies providing system flexible LED Pixel strings.
U.S. Pat. No. 5,330,368 discloses a flat bundle of cables are each sheathed with an electrically insulative synthetic resin and arranged in a spaced relationship while extending in parallel with each other. A plurality of baseless bulbs are arranged one after another along at least one cable of the flat bundle of cables while making electrical connection to the at least one cable via lead wires. A plurality of moldable plastic material holding structures are arranged one after another in the spaced relationship along the flat bundle of cables. Each holding structure serves to firmly hold a respective baseless bulb and the flat bundle of cables so that a central axis of the bulb extends parallel with a plane of the flat bundle of cables and perpendicular to the extending direction of the cables.
U.S. Pat. No. 6,837,598 discloses a lighting device having a three-way conductor strip with three conductors extending in an axial direction and electrically connected at intervals to LED elements arranged in a row. Each LED element is in a plastic housing which surrounds the LED and the conductor strip, is light emitting and may have a lens over the LED. The housing includes two shells fixed together, and with supporting elements therein for an LED element, an adjacent axial conductor strip area and a heat activatable electrically conductive material. The three-way conductor strip comprises a continuous positive conductor, a continuous negative conductor and an interrupted central conductor that extends from LED element to LED element.
U.S. Pat. No. 6,566,824 discloses an illumination apparatus comprises a lighting segment that includes a plurality of lighting sections. Each of the sections comprises a printed circuit board having a solid state optical emitter mounted thereon. The sections are interconnected by printed circuit board connectors, which serially position the printed circuit boards with edges of adjacent printed circuit boards proximate to each other. The connectors are deformable to alter the orientation in response to an applied force. The sections are electrically connected to each other such that the solid state optical emitters are electrically connected in series. The segment has a current regulator that controls current through the solid state optical emitter.
US2006158882 discloses a LED assembly suitable to form a string provided with an LED mounted with a mounting on a base, which base is provided with electric connection wires wherein the LED mounting and electric contacts to the connection wires are protected from the surroundings by a package of hot melt material. The invention further relates to a string of interconnected LED assemblies, preferably wherein the LED assemblies are separated from each other by length of flexible contact wires.
US2010134041 discloses a device for individually driving OLED/LED elements of an OLED/LED string, comprising for each OLED/LED element of the string: a controllable shunting switch coupled with the respective OLED/LED element, switch controller means for controlling said shunting switch and having a control output port coupled to said switch, a data input port and a clock input port, level shifting means assigned to said switch controller means and adapted to bring the control input data to a level sufficient to be accepted by the switch controller means during a programming mode and to allow the control of said shunting switch. Said switch controller means of said OLED/LED elements are provided to form a serial-to-parallel converter means.
US2009147509 discloses a lighting system and method for assembling the lighting system, wherein the lighting system includes a flexible conductive strip, a control module in electrical communication with the flexible conductive strip, and a plurality of light source modules, wherein the light source modules can be coupled to the lighting system at any desired location along the length of the flexible conductive strip.
CN101424378 discloses an LED strip and an LED screen. The LED strip comprises at least two LED units, at least one positive power line, at least one negative power line and at least one signal line, wherein each LED unit comprises at least one LED and a control module thereof. Each LED unit is provided with a light collecting part which is used for reflecting out light emitted by the LED. With the technical proposal, the LED unit can be fixed on a corresponding fixation position, the connection wires between the LED units are simpler, the LED units have higher brightness and farther illumination distance and diversified LED strips with obvious decoration effect can be formed through combination.
US2008180269A describes a lighting apparatus which includes a regulator configured to receive power, LEDs of at least two different colors, and a programmable controller. The programmable controller includes software that is configured to provide a digital pulse width signal to the LEDs in response to a data signal. Also included is according to an embodiment of the present invention is a programmable controller with non-volatile memory for storing the software, which may be upgradeable.
US2010164409 discloses LED light wires comprising a plurality of dynamically addressible LED modules, each LED module comprising one or more LEDs; a microcontroller; and one or more ports, said microcontroller being configured to: check a status of at least one of said one or more ports; if the status of the port corresponds to a predetermined state: assign the LED module to which said microcontroller belongs to a first display address, and send signals to said microcontroller of a neighboring LED module, said signals assigning respective further display address to the neighboring LED module. Such LED light wires can also include a display memory which stores current display information associated with each of said LED modules in said LED light wire, and a display controller, said display controller being configured to update the current display information stored in said display memory.
US2006022214 discloses method and systems for LED modules that include an LED die integrated in an LED package with a submount that includes an electronic component for controlling the light emitted by the LED die. The electronic component integrated in the submount may include drive hardware, a network interface, memory, a processor, a switch-mode power supply, a power facility, or another type of electronic component.
One important parameter in connection with flexible LED strings is the fact that each LED pixel should emitted dentical colors when instructed there to. For instance if two LED Pixels is instructed to emit the same red color a human should not be able to distinguish the two red colors of the LED pixels. Therefor in order to ensure initial colors of each LED pixel the flexible LED pixel string have been manufactured using bined LEDs meaning that the LED manufacture have sorted the LEDs into bins where the color of the LEDs are matched within a predetermined range. However even with bined LED its difficult to provide identical colors from the different LED pixels. Another issue is the fact that typically more than one flexible LED pixel strings are used in the installations and there is thus a change that two neighboring flexible LED pixels strings would be manufactured by using LED form different bins. In fixed installations this fact is minimized by ensuring that all the flexible LED strings in the installation have been manufactured using the same LED bins. However in the touring industry the installations are often moved and changed and it is thus impossible to ensure that all the flexible LED strings are manufactured from the same bins of LEDs.